Remediating NZ’s old buildings a growing challenge

The history of any country is a vital part of its culture that should unquestionably be preserved for future generations.

“It may be written down, but history is much more vibrantly expressed in the actual objects and institutions that speak of those former times. Museums and galleries house much of our cultural history but one of the most important expressions of our past is seen in the heritage buildings still intact around New Zealand – and their contents, often open for visitors and tourists to see,” says Kurt Downie, senior project manager for Kwanto.

Downie says our history is relatively young on a global time scale but throughout the country New Zealand has thousands of buildings, large and small, that exhibit the design, architecture and construction practices of our colonial and more recent past.

“But time and weather can be harsh on old buildings – as can the march of progress. Building materials have a finite life and the arrival of new urban developments may put older buildings at risk, though our heritage preservation laws offer some protection.

“From a financial point-of-view, the cost to modernise and maintain a heritage building, and ensure compliance with building regulations such as seismic standards, can also be high, while the income the building might generate could be quite modest or limited,” says Downie.

The ongoing plight of the St James Theatre in central Auckland highlights this dilemma. A much-loved entertainment venue, the theatre requires major remediation investment but was on course to be restored and retained before key finance fell through and its future is uncertain.

New Zealand’s recent history of earthquakes in New Zealand has also made seismic stability a more prominent requirement, both in terms of new builds and the restoration and maintenance of old ones. Added to that is an also-recent trend for sustainable options to be incorporated into the build or re-build or at least be considered.

All of which contribute to significant challenges, says Downie, for companies charged with planning and implementing the restoration, remediation, or protection of a heritage buildings.

Three key challenges Kwanto has faced in many of the remedial heritage projects undertaken are:

• the broad variety of building materials and construction methods used in these old buildings over many years

• the hidden issues – what lies unknown behind the outer facades, in ceilings and under floors

• the requirement in many cases for quite specialised building skills, such as stonemasonry, in the remediation

“For our project managers, understanding what lies behind the walls – any unknown issues like timber decay or residual asbestos – has to be factored into the project programme, while the involvement of possibly a range of specialist tradespeople requires careful co-ordination to ensure cohesive progress.

“For the quantity surveyor, there is also a degree of flexibility required until those unknown materials are revealed during investigative works prior to construction or once work begins.

“From a sustainability perspective, heritage buildings inherently apply sustainability principles in that they often require building materials that can be readily, and often only, sourced from recycling suppliers – or the existing materials can be refurbished.”

The project manager and QS can also enhance the sustainability values of the project by building environmental and sustainability goals into the plan and clarifying the cost-benefits of using environmentally sustainable options.

“Working on a heritage project is immensely satisfying for many reasons. There is a deep sense of satisfaction in being part of the retention of a landmark building that people enjoy and revere, while the specialist tradespeople are often craftspeople who are aiming to recreate or revive our history. They are carrying on a rich tradition and are themselves an important aspect of our history and culture worth preserving,” says Downie.

Kwanto has worked on a range of heritage projects in recent times, including churches, libraries and old homesteads, along with major institutions like Auckland’s Town Hall, Civic Theatre and War Memorial Museum, and a common requirement alongside upgrading and refurbishment has been seismic strengthening.